It coincides with the biggest ever food collection in the UK taking place today and tomorrow, organised jointly by the charities and supermarket chain.

More than two-thirds of families (70%) suffering from food poverty with children in primary school education were found to be relying on free school meals, breakfast and after school clubs to feed their children.

More than a quarter of parents suffering food poverty said they would not have enough food to feed their children during the approaching school summer holidays.

And parents were gloomy about their food situation in the future, with only a third expecting their situation to improve in the coming 12 months.

Rebecca Shelley, Group Corporate Affairs Director at Tesco said: "This research reveals that since our last national food collection in December, the problem of food poverty in the UK has increased and shows no signs of improving. It's hitting families hard, especially when resources like free school meals, breakfast clubs and after school clubs are not available.

"Because we have stores in so many communities across the UK, we are working with the help of our customers, thousands of our colleagues and volunteers from the Trussell Trust and FareShare to help provide emergency food to people who are struggling."

The National Food Collection will take place in every Tesco store in the country. Food donation will go towards the Trussell Trust's nationwide network of 360 foodbanks and the 900 charities supported by FareShare in the UK.

The supermarket giant has also pledged to top up total donations by a further 30%.

Lindsay Boswell, chief executive of FareShare said: "FareShare supports more than 900 frontline charities across the country by providing them with good quality, nutritious food.

"These charities offer not only a meal, but invaluable support to some of the poorest people in our society. Alarmingly, more than a third of these are organisations like breakfast and after school clubs that help feed vulnerable children.

"This collection comes at a crucial time. We fed more people than ever before last year but the demand for our services is rapidly increasing, as more people turn to charities for food than at any other time in FareShare's history. Thanks to the generous support of Tesco and their customers, we'll be able to provide them with even more at a time of urgent need."

The Trussell Trust has seen a rise in the number of people turning to it for help, with nearly 350,000 people receiving emergency food in the last year.

Chris Mould, Chairman of Christian charity the Trussell Trust said: "That one in five parents in this country are struggling to afford food for their families and thousands more people are turning to foodbanks for emergency food is a stark reminder of how tough things have become for many ordinary people.

"We're meeting parents who've gone hungry for days in order to feed their children, and school holidays are always especially difficult with many budgets stretched to breaking point. Our foodbanks across the UK are working tirelessly to meet the growing demand and the Tesco collection will provide vital supplies to help stop families going hungry this summer."